Got a '94 Yamaha 40hp in excellent shape. Well kept and not abused. What do you think is the best foot oil to use? Yamalube, Quicksilver,or synthetic Castrol,Mobil 1, Valvoline etc.? I love the green Quicksilver I put in my Mercruiser but will it matter in the Yamaha? Is Yamalube just as good or...